Dental handpiece



Dec. 1, 1931. J, R, lMPEY 1,834,157

DENTAL HANDPIECE Original Filed Jan. 7, 1929 A TTORNE Y 11 l By Patented Dec. 1, 1931 'UNITED STATES PATENT OFFICE JOHN n. may; or SAN FRANCISCO, CALIFORNIA l DENTAL lrrANnrIECE' Application mea naunmryvf1929,y serialNo. samen. Renewed Iu1y.29,-19so.

This invention relates to improvements in dental 'hand pieces, and more particularly to that hand piece illustrated in my issued Patent No. 1,479,606, dated January 1st, 1924.

The present invention also relates to a single handoperated dental hand piece, whereby the dentist is enabled to grip the sheath or spindle pulleyl with the lirstand rsecond lingers and with-the 'thumb inwardly press the operating stem when `it'is'desired'to re'- lease an implement or burr'fromthe chuck. One of the Objects Vofthis inventionis' to simplify the interior structure` of "the hand piecevby reducinglthe number ofvpart's, mak` ing them more accessible and adjustable, and` to enable the onehand piece withialsheath of fixed' length to be constructed with a spring operated wedge slide coacting with 'a lever', which'in turn operates a chuck plunger con;-v

trollingthe holding ofthe tool 'within the hand piece. [j 'I Bymy' present invention, the work of changing the tools or implements usedin a'l hand piece is materially expedited andthe loss of time in sterilizing the hands between change of tools is eliminated, as the.V pressure of the thumb or linger of the hand holding thefhand piece is all that isrequiredto release the tool. v l

With the above mentioned and other ob'- jects in view, theinvention consists in the novel construction-and combination of parts hereinafter'described, illustrated inthe ac` companying vdrawings and 'pointedout in the claims vhereto appended :fit being understood that various changes in the'form, proportion,

size and minor details of construction withinl the scope of the'fclaims maybe resorted to without vdeparting from the spirit or sacriicing any of the advantages of the jinven- To more fully comprehend the invention, reference is directed to the accompanying drawings, wherein Fig. 1 isa view 1n side' elevation of they preferred embodiment of u my invention.

Fig. 2' is a. similarjviewf'with the sheath illustrated infsection, disclosing the' spindle and the smooth face wedge slide and lever in chuck locking position.

FigQB is a longitudinal sectional view'of the spindle, illustrating the chuck plunger Operating lever andthe wedge slide in chuck releasing position.

Fig. 4 is a transverse section on line 4-4 Fig. 2, the parts being in the position to lock the implement stem. f n

Fig. 5 is a, view similar toV Fig. 4 taken on line 5 5 Fig. 2.

Fig.l 6 is a detailviewY in side :elevation ofl a modified'form of lever.l v l .A y

` In the drawings, a conventional wrist joint frame isindicated at 1, and to thisis securedv isfa chuck follower orplunger 13` lineally movable within the upper end of the chamber 10, the present plunger being illustrated as of two parts whereby to permit of the usey of oneor more shims 13a between the parts to Vcompensate for wear of the plunger and associated parts as well as to afford a very flne adJustment in order to provide for the exact amount of movement of the plunger required to properly close the` chuck.

` To actuate the chuck plunger 13, a chuck plunger Operating lever 14 is mounted within the enlarged chamber 9 in the spindle, and the same is fulcrumed at 15, the fulcrum pin extending into the walls of the slot 17. The lever is held from longitudinal movement within the chamber as it is'fulcrumed to a part which is also held from longitudinal movement within the hand piece.

The butt orbase 18 of the lever coacts with the end of the plunger 13, as in the drawings, and the endofsaid lever is offset or laterally bent at 16, to ride on the inclined or wedge surface 18of a lever actuating block 19'slidable longitudinally Within chamber 9 and attached by a pin `20 to the inner end of an operating stem 23. The stem 23 is mounted for lineal 'operating stem 23 to be applied and withdrawn without removallot the ,cambloclc 19, and also without having to disconnect the bearing member for the rear or pulley endl4 of the spindle. s 4 The upperendfof'the op'e'rating'stem cai'- ries ahead .and surrounding the stem between said head and spindlel pulley is a` coiled expansion spring 26, which normally moves said' stem outwardly to operatethe block 19; ton cause the surface 18 thereof to ride over the end oflever 14 to. cause the-chuclrplunger to operate the chuck to tightly engage the"v Stem lof the burr or implement received there- 1n. l'

. It Will thus be apparent that but one hand of' the operator is needed.- forfchangingthe implement within the hand piece, andthe hand piece need notbe Aremoved from. that y 'hand of theoperator'whiclihe uses Vin vwork-A ing on the patient. c Y Y f Y "Cooperating telescopic skirts 27 and 28, one carried by pulley 24 and the other extended from head 25 enclosel spring 26 and conceal thesame. y The hand piece is at itsinaximum normal overall. length' 'when'spring 26 is holding block'19`to cause the smooth inclined surface 18 thereof to operate lever 14 to actuatefparts' to hold the tool in clutch 12. This enables a? simplified construction ofthe sheath and a lesser number of parts than are requiredv in devices now on themarket wherein the length of the sheath is variablen-nd is of greatest length when the tool is locked and Vwherein friction' alone serves tohold the tool inlocked ,positionand the lever reciprocates withAY a part ofthe sheath. The sheath is of aiXed length, and if desirable an antifriction roller 29'may be mounted on theend of vlever 14 to reduce friction on the operation of part or block 19.

` I'claim:- j l i1". A dental hand piece includingva nonextensible sheath of alixed length, a spindle i rotatable therein, an 'implementf'holding c huck in one end of saidlspindle for operation to grip and release an implement, a lever pivoted within the spindle to cooperate with said chuck, aY partV longitudinally/,slidable within said spindle and relatively to the lever, said part provided withv a smooth inclined surface'operating onsaid lever on theV longitudinal:'sliding ofthe part Within the spindle to causethe leverftofattuate the chuck,a recipro'cable stem extendingfrom the-other end' of said sheath and operatively extending through the rear end/of the spindle andhaving` ainger piece for moving it 1ongitudinally ofthe spindle in one directionV toV ei'ect release of saidgoperatingpart, means detachably connecting thestem `With said ac-` tuating member, said meansbeing accessible through an opening formed: in the wallof the spindle and spring-means vassociatedyvith said stemvv-for-movngit in an opposite direction-whereby to y maintain the chuck clos.- ing element inoperative position.-

Sr-.1A dentalhandpiece comprising a casi ng,.ra l.spindle 'mounted for rotation within the casing, a tool holding' chuck at the forwardgellld` of the .spindle,.a part movable withinthe spindle for operating ythe chuck, a

secondpart slidably `mounted `within Athe spindle in engagementwith: the'rst mentioned part-and cooperating therewithwhen in a predetermined position to `n iaintainthe cvhuckj closed, said-second part having an operating portion extending through the rearl'end of'the spindle, spring meansV associatedwith said operating portion for holding said second part in said predetermined" position and a telescopingV housingA for said' spring means-.carried by said operating portionimf y 4. A dental-hand piece comprising a noneXtensible sheath of a fixed length, a spindle rotatable.V therein, an implement holding chuckinone end of vsaid spindle forL operation to grip. and release an implement, apart pivoted vWithin the spindle to cooperate with said chuck, a second part longitudinally slid-- able Within saidf spindlev and relativelyV to saidrst part, one of said parts'havin'g` a smooth inclined surfaceengaging' the other of said parts .whereby operation of said slidablepart within the spindle will cause the pivoted part .tov actuate the chuck, a reciprocable stem extending from said sheath and V.operatively connected with the longitudinall v slidable part, anda spring for actuating the stem in one direction to cause said longitudinally slidable part toioperate' said vpivoted part. f 1 l 5.v A dental;l hand piece comprising a casing, a spindle mounted for rotation within the casing, a'driving pulley onV the spindle, a tool holding chuck in the forwardfend of the spindle, a part movable within the spindle f for operating the chuck, a second part slidably mounted within the spindle in engagement with the first mentioned part and cooperating therewith when in a predetermined f position to maintain the chuck closed, said second part having an operating extension projecting through the pulley, a, housing comprising teleseoping sections one on the eX- f tension and the other on the pulley, and a spring within the housing between the pulley and the rst mentionedhousing sec-tion, said spring operating to -hold said second part in said predetermined position.

In testimony whereof Irhave signed my name to this specification. Y

JOHN R. IMPEY. 

